Albert herrmann



UNITED STATES ATENT FFlCE.

BLUE COLORING-MATTER.

SPECIFICATION formingpart of Letters Patent No. 567,567, dated september8, 1896.

Application filed January 11,1895. Serial No. 534,586. ($peoimens.)Patented in Germany June 6, 1893, No. 745,014,- in France July 31,1893,110- 192,8 07,a11(1i11 England July 81, 1893,N0.14,671.

To all whom it may concern:

Be it known that I, ALBERT HERRMANN, a citizen of the Empire of Germany,and a resident of I-ldchst-on-the-lVIain, in the Empire of Germany, haveinvented certain new and useful Improvements in the Production ofGreen-Blue Coloring-Matter, (for which Letters Patent Were granted to mein Germany, No. 71,014, dated June 6, 1893; in France, by Certificate ofAddition to Letters Patent No.192,807, dated July 31, 1893, and in GreatBritain, No. 11,671, dated July 31, 1803,) of which the following is aspecification.

I have discovered a method for manufacturing a fast blue acid coloringmatter. This coloring-matter consists of the sulfonic acids ofInetaoXydibenzyldiamidotriphenylcarbinol,

or metaoxydibenzyldiamidodiotolylphenylcarbinol,

C 11 OH (meta) C,H IIOC e s( 3) ormetaoxytetrabenzyldiamidotriphenylcarbinol,

The manufacture of this coloring-matter is carried out in a manneranalogous to the process described in Reissued Letters Patent granted tome on May 20, 1890, No. 11,077, Where in place of the bases mentionedthose indicated by the above formulae are used. Thus in accordance withsaid process the symmetrical metaamidodibenzyldiamidotriphenylmethane 0rsymmetrical metaamidodibenzyldiamidodi0rthotolylphenylmethane ormetaamidotetrabenzyldiamidotriphenylmethane are converted into thecorresponding metaoxyleuco bases by means of nitrous acid, or themetaoxyleuco bases are obtained by condensation of monobenzylanilin,monobenzylorthotoluidin, or dibenzylanilin with metaoxybcnzaldehyde. Theresulting metaoxyleuco bases are then sulfonated by co11- 6o centratedor fuming sulfuric acid and the leuco-sulfonic acid oxidized by peroxidof lead or similar agents.

Instead of the bases the sulfonic acid of monobenzylanilin or1nonobenzylorthotoluidin or dibenzylanilin may be condensed withmetaoxybenzaldehyde and the resulting leuco-sulfonic acids then furthersulfonated to the leuco-sulfonic acids of the blue c0loring matters, andthese oxidized to the color ing-matters.

Example: 30.4 parts, by Weight, of monobenzylorthotoluidin are dissolvedin two hundred parts, by Weight, of alcohol. To this so lutiontwenty-two parts, by Weight, of thirty- 7 one per cent. hydrochloricacid and 12.2 parts, by weight, of metaoxybenzaldehyde are added. Thissolution is boiled for tWenty-. four hours in an inverted condenser andthen the alcohol is distilled off. The residual leuco base is boiledwith much water with addition of dilute sulfuric acid, then treated Withboiling water until it reacts neutral, and finally dried on awater-bath. The sulfonation is effected by treating this leuco base withsulfurie acid, monohydrated sulfuric acid, or fuming sulfuric acid. Ithas proved most advantageous to dissolve the leuco base in five parts,by Weight, of monohydrated sulfuric acid. The product of the reaction ispoured into Water and the precipitated leuco sulfonic acid filtered offand converted into the calcium or sodium salt. This is then treated withthe calculated quantity of peroxid of lead and of a mineral acid oracetic acid. The lead is 5 precipitated from the resulting blue solutionwith Glauber salt. In the filtrate the coloring-matter is precipitatedwith salt. The solution of the coloring-matter may also be evaporated todryness.

The new coloring-matter is a copper-red powder with metallic luster. Itdissolves in water with a blue color, is Very slightly soluble inalcohol, almost insoluble in benzene and ether. The aqueous solutionbecomes green -on addition of a mineral acid. Ammonia andmetaoxybenzaldehyde, sulfonating the metaoxyleuco bases obtainedthereby, and then oxidizing the resulting leuco-sulfonic acid,substantially as set forth.

2. The process of producing fast-blue coloring-matter, which consists incondensing the sulfonic acids of monobenzylanilin or its homologues withmetaoxybenzaldehyde, then again sulfonatin g the resultingleuco-sulfonic acids whereby leuco-sulfonic acids of the bluecoloring-matter are produced, and oxidizing the latter to thecoloring-matter with a suitable reagent such as leadperoxid,'substantially as set forth.

3. As a new product, a fast-blue coloringmatter being a copper-redpowder with metallic luster, soluble in water, scarcely soluble inalcohol, insoluble in ether and benzene, dyeing wool and silk in an acidbath blue tints, the aqueous solution turning green with mineral acidand red on heating with caustic soda, substantially as set forth.

In testimony that I claim the foregoing as my invention I have signed myname in presence of two subscribing witnesses.

ALBERT HERRMANN.

WVitnesses:

HEINRICH HAHN, BERNHARD LEYDECKER.

